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You fixed it! When I check an oil fail, I list Suction, Discharge, Net oil pressure, superheat at compressor, oil level in each compressor, oil level in oil reservoir (if one), oil differential from oil reservoir to oil level controls (if any). Oil separator line is feeding, pick up screen is clean. oil level control screen is clean. Wires are tight, contactor is good Amp draw. no logging in heat reclaim, refrigerant level, what other work has been done lately. A always do something like change the contactor, then I go home and hope and perhaps got lucky. Good luck.

mccann I did all of the above except changing the contactor. Maybe I got lucky anyway. Side note: why does contactor always come up as a misspelled word on these post?

Originally Posted by mccann

You fixed it! When I check an oil fail, I list Suction, Discharge, Net oil pressure, superheat at compressor, oil level in each compressor, oil level in oil reservoir (if one), oil differential from oil reservoir to oil level controls (if any). Oil separator line is feeding, pick up screen is clean. oil level control screen is clean. Wires are tight, contactor is good Amp draw. no logging in heat reclaim, refrigerant level, what other work has been done lately. A always do something like change the contactor, then I go home and hope and perhaps got lucky. Good luck.

I don't know why it stopped tripping on oil pressure but I am glad it did. Nothing changed that I can see so it remains a mystery. Indy what do you mean by I should have seen it after 10 mins of run time? All of the safeties (high pressure, low pressure, oil pressure and motor over load protector) are wired in series with the contactor coil.

Last edited by welling service; 12-01-2012 at 12:18 AM.
Reason: add a word

I don't know why it stopped tripping on oil pressure but I am glad it did. Nothing changed that I can see so it remains a mystery. Indy what do you mean by I should have seen it after 10 mins of run time? All of the safeties (high pressure, low pressure, oil pressure and motor over load protector) are wired in series with the contactor coil.

You should have seen the drop in net oil pressure, with in ten minutes.

I don't believe the oil press suddenly dropped as soon as you left.
If the compressor goes off on internal overload the oil fail will trip.

When the overload condition automaticcaly resets, the manual reset of the oil fail is needed.

I did see a drop in net oil pressure within 5 mins. from about 50 psi down to 15 psi. You might have something on the internal overload thing. Haven't thought of that but the comp. never runs hotter than normal. I should have checked amp draw but never saw any reason too.

Originally Posted by indy2000

You should have seen the drop in net oil pressure, with in ten minutes.

I don't believe the oil press suddenly dropped as soon as you left.
If the compressor goes off on internal overload the oil fail will trip.

When the overload condition automaticcaly resets, the manual reset of the oil fail is needed.